style: Address review nits

- Remove redundant extension from filename (was: block_png_uuid.png, now: block_uuid.png)
- Use lazy logging format instead of f-string

autogpt_platform/backend/backend/api/features/chat/tools/binary_output_processor.py

@@ -225,12 +225,12 @@ async def _save_binary(
 
     try:
         safe_block = sanitize_filename(block)[:20].lower()
-        filename = f"{safe_block}_{ext}_{uuid.uuid4().hex[:12]}.{ext}"
+        filename = f"{safe_block}_{uuid.uuid4().hex[:12]}.{ext}"
 
         file = await wm.write_file(content, filename)
         ref = f"workspace://{file.id}"
         cache[content_hash] = ref
         return ref
     except Exception as e:
-        logger.warning(f"Failed to save binary output: {e}")
+        logger.warning("Failed to save binary output: %s", e)
         return None